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Introduction Selection of optimal out-of-hospital cardiac arrest patients (OHCA) for conveyance to specialist cardiac arrest centres remains challenging owing to unpredictable neurological recovery and delays in formal neuroprognostication. Several models, including the OHCA score, CAHP score, and MIRACLE 2 score, are accurate risk stratification tools but rely on index blood gas analysis which can be a challenge to measure in a pre-hospital setting. A simplified pre-hospital risk tool is required to select pre-hospital interventions, prioritisation for expedited conveyance to cardiac arrest centres and to avoid unnecessary secondary transfers.This study evaluates an adjusted MIRACLE2 score, titled the Pre-MIRACLE2 score which is modified to exclude pH criteria, and its prediction of neurological outcome after OHCA.Methods A multicentre retrospective study was conducted across a cardiac arrest centre and five district hospitals (January 2019–October 2024). Patients aged ≥18 years with presumed cardiac or medical aetiology OHCA, ROSC (return of spontaneous circulation) and survival to hospital admission were included. The Pre-MIRACLE 2 score (calculated without pH) was calculated. Score performance was estimated by receiver operator characteristic (ROC) curves and estimation of the area under the curve (AUC). Risk groups were classified as low risk (0–2), intermediate risk (3–4) and high risk (≥5). The primary endpoint was poor neurological outcome at hospital discharge (cerebral performance category 3–5).Results Among 635 patients (median age 66 years, 72.1% male), 38.8% survived to discharge, while 16.3% had poor neurological outcomes (CPC 3–5). 21.1% had an initial shockable rhythm, 86.2% were witnessed and 73.3% had bystander cardiopulmonary resuscitation (CPR). Poor neurological outcome occurred in 73.8% of patients.Complete Pre-MIRACLE2 scores were available in 476 (67.6%) of patients. The pre-MIRACLE2 score had an AUC of 0.79 (95% CI 0.74–0.82). Patients in the low-risk group had a 28.4% risk of poor outcome, intermediate risk had a 70.7% risk and patients in the high-risk group had an 88.4% risk poor outcome.A higher Pre-MIRACLE2 score was associated with increased risk of:Withdrawal of treatment (OR 5.7, 95% CI: 3.51–9.49, p<0.001)Prolonged hospital stay (≥21 days) (OR 2.35, 95% CI: 1.57–3.54, p<0.001)Prolonged ICU stay (≥10 days) (OR 1.77, 95% CI: 1.11–2.85, p=0.017)In-hospital mortality (OR 0.08, 95% CI: 0.05–0.11, p<0.001)Abstract 2-035 Figure 1Abstract 2-035 Figure 2Conclusions The Pre-MIRACLE 2 score, excluding index blood gas analysis, is practical to calculate and has good prognostic value in predicting neurological and survival outcomes in OHCA patients. Its application in pre-hospital settings may aid in early risk stratification, aiding prioritisation of patients for direct conveyance to a cardiac arrest centre for cardiovascular therapies, reducing unnecessary inter-hospital transfers with the potential for improving outcome in this patient cohort.